Maintain remember me state on password change

Fix regression from https://gerrit.wikimedia.org/r/#/c/94614/

Ensure that when users login with "remember me" selected, they get a
new remember me token after changing their password.

Change-Id: Ibbf0d823bd5ef5304bf6ad1b67966d18dfb3580c

includes/specials/SpecialChangePassword.php

@@ -296,7 +296,8 @@ class SpecialChangePassword extends FormSpecialPage {
 		if ( $isSelf ) {
 			// This is needed to keep the user connected since
 			// changing the password also modifies the user's token.
-			$user->setCookies();
+			$remember = $this->getRequest()->getCookie( 'Token' ) !== null;
+			$user->setCookies( null, null, $remember );
 		}
 		$user->resetPasswordExpiration();
 		$user->saveSettings();